1. Field of the Invention
This invention relates to dispensing closures for storing and dispensing particulate matter, in general, and, more particularly, to plastic closures having hinged reclosable flaps.
2. Description of the Related Art
Food product container closures having hinged reclosable flaps are known in the art. For example, flapper-cap container closure patents assigned to Gateway Plastics Inc. of Wisconsin include U.S. Pat. Nos. 6,250,517; 6,308,870; 6,460,718; 6,464,113; 6,691,901; D509,426; D513,452; and 7,007,830. Flapper cap patents assigned to Weatherchem Corporation of Ohio include U.S. Pat. Nos. 4,936,494; D340,187; 5,330,082; and RE37,634. Common to their descriptions is the providing of a cover-lid with a first flap overlying a single large dispensing aperture and a second flap overlying a series of smaller dispensing apertures. As will be appreciated, the smaller apertures are utilized as sifters for shaking matter from the container, while (depending on size) the larger aperture allows for spooning matter out of the container, or for using it as a pour spout. Also common to these container configurations are the inclusion of a pair of toggle hinges, to open and then reclose each of the flaps in turn.
Experience with these double-hinge, double-flap constructions, however, has shown that they exhibit several problems. First, the flaps tend not to stay closed, but often pop open so that the particulate matter within is not always sealed. Second, their methods of injection mold manufacture are complicated, and frequently lead to substantial differences in the shrinkages of their respective parts. This causes the closure to go out of round when attempting to screw it onto the container or bottle beneath.
However, and as will be appreciated by those skilled in the art, the container closure of the present invention allows for a simpler molding manufacture, a more effective seal, and a more reliable use of operation. As will be seen, this follows, in part, from the use of a further toggle hinge, resulting in a triple-hinge, triple-flap closure.